The present invention relates to a microprogrammable preprocessor for interfacing between a multiplicity of data communications lines and a central microprogrammable processor by tending to the detailed line procedures and requiring central processor intervention on a message basis only.
A data processing communications system generally includes a central processing unit (CPU) and a plurality of data communications channels including direct connect lines, MODEMS, and the like. As the system becomes more complex, inefficiencies increase as the CPU data processing functions are interrupted more frequently for line procedures and data communications details. The addition to the system of a microprocessor to handle line procedures and details may relieve the CPU of these burdens but may otherwise limit the data communications aspects of the system to the necessarily limited capabilities and throughout speed of the microprocessor.